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    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>基本语法</title>
    <script>
        //1-申明变量和赋值
        // 变量var ---es5
        // 变量let ===es6

        //先声明 后赋值
        let a;
        a=1;
        console.log(a);

        //同时声明，赋值
        let b=2;
        console.log(b);

        let x

        //不声明，直接赋值
        x=88;
        console.log(x);
    </script>
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<body>
    
</body>
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